Brake



May 28, 1929. F, E, JONES ET AL ,7l4,9ll

BRAKE Fle'cl March l0, 1924 2 Sheets-Sheet l May 28, 1929. F. E. JONESET A1.

BRAKE Filed March lO, 1924 2 Sheets-Sheet 2 WIII llatented May P28,1929.

:FRED E. JONES, OE DETROIT, AND MONTGOMERY W. MCCONNEY, or E'ERNDA'LE,NICH- IGAN, AssIGNORs To GENERAL MOTORS CORPORATION, or DETROIT,IaIOHIeAN,- A

CORPORATION F DELAWARE.

BRAKE.

Application med Narch 1o, 1924. 'serial No. 598,091.

This invention relates to brakes, and is .illustrated as embodied in anautomobile chassis having brakesy on all four yonli its Y wheels'.

5 .Heretofore the onl practicable non-skiderated centrifugally byrotation of the Wheel,

ding brakes, i. e. bra es releasin automati-l cally in case of skidding,are of t e type uti; lizing as a brake drum a floating ring frictionallyclutched to the wheel by means opthe ring or drum. thus beingdisconnected from the Wheel in case of skidding. While these brakes arein the main satisfactory, it is one object of the present invention toprovide a non-skidding brake of a different type, lighter and lessexpensive, while at the same-time more sensitive to changes in the speedof rotation of the wheel, by providing rotation-controlled means (shownas a cen- 20 trifugal governor geared to the wheel to rosion to abrake-,operating cylinder of compressure.

pressed exhaust gases Orother fluid under v controlling the compressedases by a floating valve, preferably in the orm of a piston,v operatedyieldingly by a spring and arranged to yield against the resistance ofthe spring to cut 0E the gases when-they reach description of oneillustrative embodiment y shown-in the accompanying drawings, in

which:

Figure 1 is a diagrammatic longitudinal vertical section through anautomobile chassis' igure 2 is a view` on a largescale showing, partlyin side elevation and partly in vertical section, the connectionsimmediately adjacent the brake pedal;

Figure 3 is ajside elevation, with the axle shown in section, lookingoutward at one of the front brakes; and V Flgure 4 is agenerallyhorizontal 4section on the line 4 4 of Figure 3, showing thecentrifugal governor and its connections.

In the arrangement selected for illustraby springs on front and rearaxles carrying front Wheels 12 having brakes 14, and rear wheels 16having brakes 18. The'brakes are intended to be actuated ordinarily bycompressed gases taken from one cylinder of the engine 20 through acheck valve 22 and stored under pressure in a reservoir 24 serving as asource of power for the brakes.

The rear brakes 18 are connected by links 26 and 28 with one end of abellcrank lever 30 having a lug 32 carrying an adjustable sto 34 in thepath of a projection on the pe al 36, so that if for any reason power isnot available, therear brakes can be set by f foot power, after a shortlost motion .ofthe pedal. The pedalis provided with the usual returnspring, not shown.

An arm 38of bellcrank lever 30 ,is connectedby a connecting rod 40 witha piston feature of the invention relates to 42 in an operating cylinder44, for rpower operation .of the rear brakes. 'Admission'o'f thecompressed gases from-reservoir 24 to cylinder 44 through conduit 46 iscontrolled by a hollow `valve pist-on 48 arranged, when moved to theright in Figure 2, first toclose an exhaust port 50 and then to bring aport 52 in its side wall into registry with an intake port 54communicating with conduit '46. Valve piston 48 is, operatedyieldinglyby a spring 56 engaged by astop 58 adjustably threaded on aconnecting rod 6() pivoted to an extension at the bottom of pedal 36.Preferably rod 60 extends through the head of4 piston 48and has a nut.62to bring the piston positively to its initial or idle position when thepedal is released, thus guarding againstA the valve sticking.

' In the operation of' the above `described tion, the invention isembodicdin an automobile chassis including a frame 10 supported parts,depression of pedal 36 acts through spring 56 to move piston 48, lirstclosing exhaust port 50 and then .openingintake port 54. Compressedgases entering from reservoir 24 push upwardly on piston 42, applyingvthe rear brakes. As soon as the reaction on piston 48 from the gases incylinderI 44 equal's the pressure on spring 56 from the pedal,

or as soon as the braking pressure is a predertermined multiple of thepedal pressure, pis-f J ton 48 is moved to the left to compress spring56, closing the intake port 54 and balancing.

with both ports 54 and 50 closed. If thepedal pressureis increased,intake port 54 again opens until a new balance is'obtained; 1f it 1o isrelieved, exhaust port 50 opens temporarily until the valve lowerpressure; i

Each front brake has an operating toggle lever`64 of usual forni,connected by a con- `necting rod 66 with a piston 68 in Aan oper- 7ating cylinder 70 connected to cylinder 44, by a iiexible conduit 72.`The cylinder 70 forms part of a casting having a iange or plate portion74 arranged to-be secured to the dust plate 7 6 of brake 14 by screws78.

' The casting is formed with a passage 80 be- .tween conduit 72 andcylinder 7.0 and with/ a bore for a valve 82 controlling this passage.The valve 82 has a diametric passa'ge 84 arranged in oneposition to'place cylinder 70 in communication with the atmosphere to exhaust thecylinder, and also has a circumferentilal passage 86 which is closedwhen passage 84 is open,fand which when-open places cylinder 70 incommunication with con-v duit72.

Valve 82 is urged angularly toward exhaust orv closed position 'byaspring'88 attached to an arm 90, and is turned against the resistance ofthe spring in a -clockwise direction toward openv position byan arm 92engaged by a Apivoted yoke94 straddling acentral boss 96 ,in which ispinned a supporting bolt 98 for the governor mechanism. Yoke 94 ispivoted to the opposite side of the casting at 100. It is operated by athrust bearing 102 engaged-'by balls 104 forming part of a centrlfugalgovernorof the well.- known ballftypel Each of the balls 104 A.isconfined in a wedge pocket in a stam ing 106 secured to a gear 108meshing wit an internal gear 110 carried by the brake drum. Gear-,108'rotateson a bearing 112 on bolt 98, where it is heldby a castellatednut 114, 'and has a sleeve portion 116 abuttingagainst the boss 96 andwhich serves to receive balls 104 and the adjacent part of the thrustbearing 102. It will'gbe seen'that the above described casting, with,the brake cylinder and piston again balances at the 1 !5'5l piston,valve, governor, and gear 108, forni va sub-assembly which is attachableand -re' l movable as a`unit.

Inoperation, if the Wheel is not turning, spring 88 holds the arts inthey -ositionS shown.l in Figure 4, with valve 82 in clo'sed or exhaustpositionso that the brake cannot be applied. This is satisfactory 4inpractice,

since when the car is standing-still the rear wheel brakes are ample'tohold the car. If the car 1s moving, with the wheel turning,

tions control ed by the governor for-.rendere ing the retarding meansoperatlve or 1n ymeans for applying the retardin'g means,

gear 108, whichl is relatively small, is driven at a high rate of speedby the relatively large gear 110, and the balls 104 are forced outwardlyby centrifugal force in their wedge pockets, rocking yoke 94and arm 92to open valve 82, thus placing cylinder in communicationwith cylinder44. Now if the brake pedal be depressed the front brakes as wellas therear. brakes will vbe applied. If the wheelskids, i. e. stops rotating,whether because of .a greasy pavement or because of excessive brakingfriction, spring 88 is permitted to turn the valve 82 toits originalposition. If the brake is not at thatitime on, this merely prevents itsapplication; if the brake is on, this automatically releases it untilthe wheel is again rotating.

While one Aillustrative embodiment of our invention has been describedin detail, itis not ,our 4intention to limit its scope to thatembodiment, or otherwise than by the terms of' the appended claims..

F We claim:

1. A vehicle comprising, in combination, a wheel, a brake for'the wheel,a source of Huid power, a conduit connecting said source tio the braketo operate the brake, a valve in the, conduit to control the applicationof power to the brake, a spring urging the lvalve in a 4direction toshut-olf the conduit to re- '95 lease the brake, and a device operatedvby the rotation of thewheel and opening Athe valve against thevresistance of the spr-ing.

2. A vehicle comprising, in combination, a wheel, a brake for the wheel,a source of fluid power, a conduit connecting said source to the braketo operate the brake, a valve -in l the conduit to control theapplication of power to the brake, a spring-urging the valve in adirection to shut olf the conduit'to release the brake, a centrifugaldevice operated by.

lthe rotation of the wheel, and a connection operated by the centrifugaldevice for opening the valve against theresistance of the Spring 3. Abrake comprising, in combination,- a rotary member,.vretarding meanscontrolling said member, a manually operablemeans to apply said'retarding means, a governor v geared solelyto said .member,..and'connec.

operative. l

7,4. Abrake comprising, in combination, a rotary member, a centrifugalgovernor geared to said member and driven thereby at a substantiallygreater speed, retarding means:V operating on the rotary member,

and a device operated by the governorand controlling the retardingmeans. 5. A- brake comprising, in combination, a rotary member, arelatively large gear turning" with said -member, a centrifugalgowernor, a small gear driving the governor and .lao

. directly and independently geared to one of said wheels and driven ata substantially higher speed than the wheel, a. manually operable brakefor the wheel, means controlled by the governor to render the brakeoperative whenever the wheel rotates but inoperative whenever the wheelis at rest.

7. A vehicle comprising, in combination, a road wheel, a centrifugalgovernor geared to the wheel and driven at a substantially higher speedthan the wheel, a manually operable brake for the wheel controlled bythe governor, and a connection from the governor controlling applicationof the brake to relieve the braking force when the wheel skids.

8. A vehicle comprising, in combination, a road wheel having a brake,manually operable' means for applying said brake, a-centrifugal governorgeared to the wheel, a fluid cylinder and piston for applying the brake,a valve permitting application of the brake in a first position andpreventing application of the brake in a second position, and aconnection from the governor for moving the valve from its second to itsfirst position when the governor is driven by the wheel at a substantialspeed. f

9. A controlling unit comprising, in combination, a supporting plate, agear supported by the p1atea centrifugal governor between the ear andplate, a power cylinder carried by t e plate, and a valve connected tothe governor and controlling the admission of power fluid to thecylinder.

10. A vehicle comprising, in combination, front and rear wheels havingbrakes, drivercontrolled means for applying all four brakes, and adevice operated by rotation of `each front wheel and constructed andarranged to control the corresponding front brake independently of thepressure exerted by said means.

In testimony whereof we aliix your signa tures.

FRED E. J ONES.4

MONTGOMERY W. MGCONKEY.

